Finding the Fourth Proportional to 2,113.59, 3,172.61 and 1,728.03

Step by Step Solution

1. Step 1: Write the proportion equation
   2,113.59 : 3,172.61 = 1,728.03 : x
2. Step 2: Convert to fraction form
   2,113.59/3,172.61 = 1,728.03/x
3. Step 3: Cross multiply
   2,113.59x = 3,172.61 × 1,728.03
4. Step 4: Simplify right side
   2,113.59x = 5,482,365.26
5. Step 5: Solve for x
   x = 5,482,365.26/2,113.59
6. Step 6: Final answer
   x = 2,593.86